[PATCHv6 2/7] crypto: sa2ul: Add crypto driver
Nathan Chancellor
natechancellor at gmail.com
Fri Aug 21 18:17:29 EDT 2020
On Mon, Jul 13, 2020 at 11:34:22AM +0300, Tero Kristo wrote:
> From: Keerthy <j-keerthy at ti.com>
>
> Adds a basic crypto driver and currently supports AES/3DES
> in cbc mode for both encryption and decryption.
>
> Signed-off-by: Keerthy <j-keerthy at ti.com>
> [t-kristo at ti.com: major re-work to fix various bugs in the driver and to
> cleanup the code]
> Signed-off-by: Tero Kristo <t-kristo at ti.com>
> ---
> drivers/crypto/Kconfig | 14 +
> drivers/crypto/Makefile | 1 +
> drivers/crypto/sa2ul.c | 1388 +++++++++++++++++++++++++++++++++++++++
> drivers/crypto/sa2ul.h | 380 +++++++++++
> 4 files changed, 1783 insertions(+)
> create mode 100644 drivers/crypto/sa2ul.c
> create mode 100644 drivers/crypto/sa2ul.h
<snip>
> diff --git a/drivers/crypto/sa2ul.c b/drivers/crypto/sa2ul.c
> new file mode 100644
> index 000000000000..860c7435fefa
> --- /dev/null
> +++ b/drivers/crypto/sa2ul.c
> @@ -0,0 +1,1388 @@
<snip>
> +static int sa_run(struct sa_req *req)
> +{
> + struct sa_rx_data *rxd;
> + gfp_t gfp_flags;
> + u32 cmdl[SA_MAX_CMDL_WORDS];
> + struct sa_crypto_data *pdata = dev_get_drvdata(sa_k3_dev);
> + struct device *ddev;
> + struct dma_chan *dma_rx;
> + int sg_nents, src_nents, dst_nents;
> + int mapped_src_nents, mapped_dst_nents;
> + struct scatterlist *src, *dst;
> + size_t pl, ml, split_size;
> + struct sa_ctx_info *sa_ctx = req->enc ? &req->ctx->enc : &req->ctx->dec;
> + int ret;
> + struct dma_async_tx_descriptor *tx_out;
> + u32 *mdptr;
> + bool diff_dst;
> + enum dma_data_direction dir_src;
> +
> + gfp_flags = req->base->flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
> + GFP_KERNEL : GFP_ATOMIC;
> +
> + rxd = kzalloc(sizeof(*rxd), gfp_flags);
> + if (!rxd)
> + return -ENOMEM;
> +
> + if (req->src != req->dst) {
> + diff_dst = true;
> + dir_src = DMA_TO_DEVICE;
> + } else {
> + diff_dst = false;
> + dir_src = DMA_BIDIRECTIONAL;
> + }
> +
> + /*
> + * SA2UL has an interesting feature where the receive DMA channel
> + * is selected based on the data passed to the engine. Within the
> + * transition range, there is also a space where it is impossible
> + * to determine where the data will end up, and this should be
> + * avoided. This will be handled by the SW fallback mechanism by
> + * the individual algorithm implementations.
> + */
> + if (req->size >= 256)
> + dma_rx = pdata->dma_rx2;
> + else
> + dma_rx = pdata->dma_rx1;
> +
> + ddev = dma_rx->device->dev;
> +
> + memcpy(cmdl, sa_ctx->cmdl, sa_ctx->cmdl_size);
> +
> + sa_update_cmdl(req, cmdl, &sa_ctx->cmdl_upd_info);
> +
> + if (req->type != CRYPTO_ALG_TYPE_AHASH) {
> + if (req->enc)
> + req->type |=
> + (SA_REQ_SUBTYPE_ENC << SA_REQ_SUBTYPE_SHIFT);
> + else
> + req->type |=
> + (SA_REQ_SUBTYPE_DEC << SA_REQ_SUBTYPE_SHIFT);
> + }
> +
> + cmdl[sa_ctx->cmdl_size / sizeof(u32)] = req->type;
> +
> + /*
> + * Map the packets, first we check if the data fits into a single
> + * sg entry and use that if possible. If it does not fit, we check
> + * if we need to do sg_split to align the scatterlist data on the
> + * actual data size being processed by the crypto engine.
> + */
> + src = req->src;
> + sg_nents = sg_nents_for_len(src, req->size);
> +
> + split_size = req->size;
> +
> + if (sg_nents == 1 && split_size <= req->src->length) {
> + src = &rxd->rx_sg;
> + sg_init_table(src, 1);
> + sg_set_page(src, sg_page(req->src), split_size,
> + req->src->offset);
> + src_nents = 1;
> + dma_map_sg(ddev, src, sg_nents, dir_src);
> + } else {
> + mapped_src_nents = dma_map_sg(ddev, req->src, sg_nents,
> + dir_src);
> + ret = sg_split(req->src, mapped_src_nents, 0, 1, &split_size,
> + &src, &src_nents, gfp_flags);
> + if (ret) {
> + src_nents = sg_nents;
> + src = req->src;
> + } else {
> + rxd->split_src_sg = src;
> + }
> + }
> +
> + if (!diff_dst) {
> + dst_nents = src_nents;
> + dst = src;
> + } else {
> + dst_nents = sg_nents_for_len(req->dst, req->size);
> +
> + if (dst_nents == 1 && split_size <= req->dst->length) {
> + dst = &rxd->tx_sg;
> + sg_init_table(dst, 1);
> + sg_set_page(dst, sg_page(req->dst), split_size,
> + req->dst->offset);
> + dst_nents = 1;
> + dma_map_sg(ddev, dst, dst_nents, DMA_FROM_DEVICE);
> + } else {
> + mapped_dst_nents = dma_map_sg(ddev, req->dst, dst_nents,
> + DMA_FROM_DEVICE);
> + ret = sg_split(req->dst, mapped_dst_nents, 0, 1,
> + &split_size, &dst, &dst_nents,
> + gfp_flags);
> + if (ret) {
> + dst_nents = dst_nents;
This causes a clang warning:
drivers/crypto/sa2ul.c:1152:15: warning: explicitly assigning value of
variable of type 'int' to itself [-Wself-assign]
dst_nents = dst_nents;
~~~~~~~~~ ^ ~~~~~~~~~
1 warning generated.
Was the right side supposed to be something else? Otherwise, this line
can be removed, right?
> + dst = req->dst;
> + } else {
> + rxd->split_dst_sg = dst;
> + }
> + }
> + }
> +
> + if (unlikely(src_nents != sg_nents)) {
> + dev_warn_ratelimited(sa_k3_dev, "failed to map tx pkt\n");
> + ret = -EIO;
> + goto err_cleanup;
> + }
> +
> + rxd->tx_in = dmaengine_prep_slave_sg(dma_rx, dst, dst_nents,
> + DMA_DEV_TO_MEM,
> + DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
> + if (!rxd->tx_in) {
> + dev_err(pdata->dev, "IN prep_slave_sg() failed\n");
> + ret = -EINVAL;
> + goto err_cleanup;
> + }
> +
> + rxd->req = (void *)req->base;
> + rxd->enc = req->enc;
> + rxd->ddev = ddev;
> + rxd->src = src;
> + rxd->dst = dst;
> + rxd->iv_idx = req->ctx->iv_idx;
> + rxd->enc_iv_size = sa_ctx->cmdl_upd_info.enc_iv.size;
> + rxd->tx_in->callback = req->callback;
> + rxd->tx_in->callback_param = rxd;
> +
> + tx_out = dmaengine_prep_slave_sg(pdata->dma_tx, src,
> + src_nents, DMA_MEM_TO_DEV,
> + DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
> +
> + if (!tx_out) {
> + dev_err(pdata->dev, "OUT prep_slave_sg() failed\n");
> + ret = -EINVAL;
> + goto err_cleanup;
> + }
> +
> + /*
> + * Prepare metadata for DMA engine. This essentially describes the
> + * crypto algorithm to be used, data sizes, different keys etc.
> + */
> + mdptr = (u32 *)dmaengine_desc_get_metadata_ptr(tx_out, &pl, &ml);
> +
> + sa_prepare_tx_desc(mdptr, (sa_ctx->cmdl_size + (SA_PSDATA_CTX_WORDS *
> + sizeof(u32))), cmdl, sizeof(sa_ctx->epib),
> + sa_ctx->epib);
> +
> + ml = sa_ctx->cmdl_size + (SA_PSDATA_CTX_WORDS * sizeof(u32));
> + dmaengine_desc_set_metadata_len(tx_out, req->mdata_size);
> +
> + dmaengine_submit(tx_out);
> + dmaengine_submit(rxd->tx_in);
> +
> + dma_async_issue_pending(dma_rx);
> + dma_async_issue_pending(pdata->dma_tx);
> +
> + return -EINPROGRESS;
> +
> +err_cleanup:
> + dma_unmap_sg(ddev, req->src, sg_nents, DMA_TO_DEVICE);
> + kfree(rxd->split_src_sg);
> +
> + if (req->src != req->dst) {
> + dst_nents = sg_nents_for_len(req->dst, req->size);
> + dma_unmap_sg(ddev, req->dst, dst_nents, DMA_FROM_DEVICE);
> + kfree(rxd->split_dst_sg);
> + }
> +
> + kfree(rxd);
> +
> + return ret;
> +}
Cheers,
Nathan
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